import java.util.Scanner;

public class AverageMeriage {
    public static void main(String[] args) {
        Scanner average = new Scanner(System.in);
        System.out.println("请输入a、b、c、d四位同学的平均分给");

        int a = average.nextInt();
        int b = average.nextInt();
        int c = average.nextInt();
        int d = average.nextInt();

        double sum = 0;

        sum = (a+b+c+d)/4;
        System.out.println("平均分是："+sum);



    }
}
